Thread-tension device.



e. w. BARROWS. v

THREAD TENSION DEVICE.

APPLICATION FILED MAY 21, 1914.

' 2 SHEETS-SHEET 1.

THE COLUMBIA PLANOBRAFH F0. WASHINGTON, D- C.

Patented Apr. 11, 1916.

.G. W. BARROWS.

THREAD TENSION DEVICE.

APPLICATION FILED MAYZI, 1914.

2 SHEETS-SHEET 2.

liq 18 1 59-19,

THE COLUMBIA PLANOGRAPH co wAsmNOTON, D. c.

Patented Apn'll, 1916.

GEORGE WILLIAM BARROWS, OF NOTTINGHAM, ENGLAND.

THREAD-TENSION DEVICE.

Specification of Letters Patent. Patented A 11 191&

Application filed May 21, 1914. Serial No. 840,065.

To all whom it may concern:

Be it known that I, GEORGE WILLIAM BARROWS, a subject of the King ofGreat Britain, and a resident of the city of Nottingham, in the countyof the said city, England, have invented new and useful Improvements inThread-Tension Devices, of which the following is a specification.

This invention relates to improvements in single spring wire tensiondevices applicable to bobbins and carriages, bobbinless carriages, andsimilar thread carriers used in twist lace machines, and has referenceto tension devices in which the free end of a spring wire, or a plateattached to such pire, is movable relatively to a nipping surace.

The present invention has for its object the production of a singlespring wire tension device in which the free end of a spring,

or a plate attached to such spring, is moved over, or across, a nippingsurface by the forward movement of the thread, the parts being soarranged thatthe distance between the spring, or the plate attached tosuch spring, and the nipping surfaces is varied by and through suchmovement of the spring.

In the drawings :.Figure 1 is the elevation of a thread carrier fittedwith one form of the improved thread tension device. Fig. 2 is the frontelevation of a device provided with a spring wire and an inclinednipping surface. Fig. 3 is an end elevation of the same. Fig. 4 is anelevation illustrating the'application of a guide or guard for thespring wire. Fig. 5 is the front elevation of a device provided with aspring wire and a flat nipping surface. Fig. 6 is'an end elevation ofthe same. Fig. 7 is an end elevation showing the combination of a flatnipping surface and an inclined bearing for the wire. Fig. 8 is thefront elevation of a device in which the thread passes through thecarrier. Fig. 9 is a sectional elevation of the same. Fig. 10 is thefront elevation of a device in which the thread passes over or aroundthe spring wire and through the carrier. Fig. 11 is a sectionalelevation of the same. Fig. 12 is a front elevation to an enlarged scaleof the tension device shown in Fig. 1. Fig. 13 is a sectional elevationof the same. Fig. 1a is the front elevation of a modified form of thedevice shown in Fig. 12. Fig. 15 is a sectional elevation ofthe same.Fig.- 16 is a front elevationof another modification of the device shownin Fig. 12, with one nipping surface removed. Fig. 17 isa sectional endelevation of the same, andFigs. 18 and 19 are diagrammatic illustrationsof different shaped nlpping surfaces.

In-thread carriers of the type shownin Fig. 1, and adapted for use inlevers, gothrough, and curtain lace machines there is a thln metal plateor carriage 1 which has a central hole, for receiving the threadedholder or bobbin 2. In thread carriers of the type used in plain netlace machines there is a carriage and bobbin similar to those shown inFig. 1, but the carriages are driven by tabs or teeth on the lower edgeinstead of the side tabs 3 as shown in Fig. 1. The thread tensiondevices hereinafter described are applicable to all the above mentionedtypes of thread carriers, and fitted with a rotatable, or fixed threadholder.

In the arrangement shown in Figs. 2 and 3, there is a single spring wire4 which is securely attached at its end 5 to the thread carrier 1. Thefree end 7 of the wire 4 normally rests upon, or is close to, aninclined nipping surface 8 which is inclined as shown relatively to thedirection of movement of the thread a, indicated in this and otherfigures by an arrow 9. This device may be fitted with a-guide or guard11, Fig.

4, for protecting the free end of the spring wire and preventingaccidental movement of the same.

In the arrangement shown in Figs. 5 and 6, there is a flat nippingsurface 12 and the wire 13 is so fixed at its end 14 that it tends tomove in the direction of the line 15, Fig. 6, relatively to thenippingsurface,or, as shown in Fig. 7 there is a flat nipping surface 12 and aninclined rest or guide 17 by which the distance between the free end ofthe wire and the nipping surface 12 is varied as the end of the wire ismoved across such nipping surface.

In the arrangement shownin Figs. 8 and 9 the wire 18 and nipping surface19are the same as the corresponding parts shown in Figs. 2 and 3. Inaddition there is a hole 20.through the nipping surface 19 so thatv 22in such surface, and a thread a which passes over or around the tensionwire 23. In this arrangement the tension upon the thread is partly dueto the bending of the thread around the wire and partly to the pressureof the wire upon the thread.

In the device shown in Figs. 12 and 13, the spring wire 24: is providedwith an end plate 25 which works between two fixed nipping surfaces 26and 27. In the arrangement shown the surface 26 forms part of a barwhich extends across the back of the carriage 1, Fig. 1, while thesurface 27 is at the free end of a bar attached to the front of thecarriage. This arrangement is adapted to facilitate the threading up ofthe tension device but the fixed nipping surfaces may be carried in anyother convenient manner. The edges of the plate 25 are grooved to act asguides to the thread and hold it on the plate, and the thread a ispreferably wrapped around the plate.

In the modification shown in Figs. 14: and 15, the fixed nipping surfaceis a wedge shaped finger 26 which is attached to any convenient part ofthe carriage. Working in conjunction with the finger 26 there is agrooved plate 27* carried by the spring wire 28 and shaped to press uponthe whole or part of the sides of the finger 26*. In this arrangementthe thread a passes upward and over the finger 26 and then under oneedge of the plate 27 so that the pull of the thread tends to lift theplate 27 off the finger 26.

In the arrangement shown in Figs. 16 and 17 the spring wire 29 isprovided with an upper wedge or plate 30 and a lower wedge or plate 31,and these plates work in conjunction with two fixed nipping surfaces 32and 33. In the arrangement shown one side of each of the wedges 30 and31 is vertical and these faces work in conjunction with vertical faceson the plates 32 and 33. Inclined faces are also formed on the plates 32and 33 to correspond with the inclined faces of the wedges 30 and 31,and the thread a is passed between the inclined faces of the wedges andthe plates.

In all arrangements herein shown and described the spring wire, or theplate attached thereto, may work in connection with straight inclines asshown in Fig. 18, or with curved or cam shaped inclines of the kindshown in Fig. 19, and when the latter type is used the incline may beshaped to give a difiering variation in the tension for equal distancesmoved by the spring over the nipping surface.

In the various tension devices herein described the wire spring may beof any suitable section and may be fastened to the thread carrier byclips, riveting, soldering, or other similar means, and the end of thewire may act upon the thread, or it may be flattened or be otherwiseshaped, or be provided with a roller, or with a plate as shown in someof the devices. The thread may pass between the spring or plate and thenipping surface, or it may make one or more half turns around the wireor plate, and when wrapped around the wire or plate the relativemovements of the thread and parts of the tension device prevent, or tendto prevent, the accumulation of flufi' upon the parts and therebyprevents, .or tends to prevent, the fluff from influencing the tensioning effects of the device.

In all the arrangements herein described the movement of the threadtends to move the spring wire, or the plate attached thereto, over thenipping surface and to such a position that the pressure of the spring,or the plate, upon the thread is reduced. The thread is suitably guidedto and from the tension device and all the edges of such de vices areshaped to prevent fraying or cutting of the thread. The spring wire maybe straight or it may be bent to suit the thread carrier to which it isapplied, and in all cases the extreme thickness of any device does notexceed the greatest thickness of the thread carrier.

I claim 1. The combination of a lace machine carriage, a thread holdermounted therein, the carriage being provided with a thread guide andwith a thread tension nipping surface rising from the carriage acrosswhich the thread passes in moving from the holder to the said threadguide, and a spring tension device secured at one end to the carriage,its opposite end being free and adapted to bear upon the thread and holdit against the said nipping surface, the thread-engaging portion of thespring tension device being movable by the forward movement of thethread in a path to vary its distance from the said nipping surface asit is moved.

2. The combination of a lace machine carriage, a thread holder mountedtherein, the carriage being provided with a thread guide and a threadtension nipping surface rising from the carriage and across which thethread passes as it moves from the thread holder to the thread guide,and a spring tension device secured at one end to-the carriage andcarrying at its other, free, end, an expanded piece bearing upon thethread and holding it against the thread nipping surface, the said freeend of the spring tension'device being movable acrossv the nippingsurface by the forward movement of the thread in a direction to vary itsdistance from the said surface as it is moved.

3. The combination of a lace machine carriage, a thread holder in suchcarriage, a fixed inclined nipping surface, a spring wire tension fingerthe free end of which is adapted to be moved by the forward movement ofthe thread across the fixed nipping surface substantially as hereindescribed.

4. The combination of a lace machine carriage, a thread holder in suchcarriage, a fixed nipping surface inclined to the face of the carriage,and a spring tension finger adapted to be moved by the forward movementof the thread in a plane which is parallel to the face of the carriagesubstantially as herein described.

5. The combination of a lace machine carriage, a thread holder in suchcarriage, double inclined nipping surfaces, a spring tension fingeradapted when in one position to press the thread into contact with oneor both of such nipping surfaces and to be moved by the forward movementof the thread away from such nipping surfaces substantially as hereindescribed.

6. The combination of a lace machine carriage, a thread holder in suchcarriage, a nipping surface inclined in one direction relatively to theface of the carriage, a nipping surface inclined in the oppositedirection relatively to the same face of the carriage, a spring wire,and a wedge shaped plate on the free end of such finger substantially asherein described.

GEORGE WILLIAM BARROWS.

Witnesses:

WILLIAM H. POTTER, SAMUEL STEVENSON.

Copies of this patent may be obtained for five cents each, by addressingthe "Commissioner or ratents, Washington, D. 0."

